Do you ever get over cheating?

When we were engaged my husband had an inappropriate relationship with one of his best female friends. They never did anything physical, that I know of. He said he was nervous about getting married..blah blah blah. Anyway, he has been faithful and great since then. Most of the time I am fine and do not think about the cheating. Some times it gets to me SO BAD I can barely function throughout the day. We have talked about it several times and I don't really know what else he can say to make me feel better. I just cannot get over it. It's been 3 years. It eats at me. We have 2 children and are very happy besides this issue. I do not worry about him cheating now, we are very different people...I just don't know what to do. We cannot afford counseling and I really don't know what to do. Those of you that have been cheated on, do you ever get over it? How?!